5 ms·
Thank god OpenBSD mixes in data from hardware RNGs, and the bootloader collects entropy as part of the boot process, effectively turning that exploit vector int
by ori_b 7y ago
Thank god OpenBSD mixes in data from hardware RNGs, and the bootloader collects entropy as part of the boot process, effectively turning that exploit vector into a state level attack.
- Dylan16807 7y agoBut if you're imaging a drive and also RDRAND fails, OpenBSD is just as vulnerable to attack. See also AMD for RDRAND failing entirely.
- ori_b 7y agoYeah, that's why the bootloader also gathers entropy as it's coming up. But, at some point nobody can save you from yourself entirely. Get a broken enough system, and every security feature will fail.
- Dylan16807 7y agoThe bootloader collects some, but I doubt it reliably collects enough all by itself.
- ori_b 7y agoHow much do you think is enough, and why do you think the amount collected during boot is insufficient?
- Dylan16807 7y agoLet's say 300 bits. I'm assuming a bootloader can't collect more in three seconds than an OS can collect in multiple minutes. Is that assumption wrong? If it's the design of the code that lets it collect entropy faster, then it's that code that needs to be ported, and it doesn't matter if it's in a bootloader or not except to save a second or two.
- vbezhenar 7y ago300 true random bits is a lot. Even something like 128 bits is unbreakable with available hardware.